Spinal damage, disease, or deformity are serious and often painful conditions that may become life-threatening conditions. Some conditions impinge on the spine and lead to pain, such as disc degeneration or tumors. Others conditions involve abnormalities, such as scoliosis or spinal stenosis, where a person's spine is more susceptible to injury or damage.
Pain is a common result from disease in, damage to, or degeneration of spinal members such as vertebrae and discs, most often from bone or tissue surrounding the spine cord impinging on the spinal cord itself. If the spinal cord is damaged, either directly or by the inability of the damaged vertebrae to protect the spinal cord, the communication between the brain and organs or limbs may be lost, resulting in organ failure or paralysis. Such conditions, if not properly managed, can lead to long-term pain, other complications, and ever-diminishing quality of life.
Many injuries to the spinal cord are not necessarily as a result of the principal injury itself. For example, an injury sustained in an accident may be one or more vertebrae being shattered or spinal discs herniated. Other times, a disc may degenerate from a minor injury sustained many years prior, or simply from the age of the body. These injuries do not necessarily impact the spinal cord in a permanent manner, other than leading to pain. The vertebral fragments or damaged nucleus will likely impinge on the spinal cord, causing pain, numbness, or reduced motor capabilities in the limbs. Removal of the impingement, and reduced swelling from the damaged or diseased tissue including the spinal cord, often promotes healing and the return of normal nervous system functioning. However, in the absence of proper medical care, a person's health may continue to degenerate, and the spine is often more susceptible to injury. In addition, the spinal cord may become permanently damaged.
The spine provides a number of specific physiological functions. The spine enables a torso to be rotated, to bend laterally, and to flex in anterior-posterior directions, or a combination of these. In addition, the spine supports the weight of the torso and the limbs attached thereto, including the head. The spine supports the body under stress or shock resulting from a person's activities such as weight-lifting, contact sports, or inadvertent accidents, though with limits. A head-on collision, such as from playing football, may result in an injured or herniated spinal disc where a portion of the spinal annulus is damaged and leaks. In addition, disease or abnormalities may be present, such as scoliosis where symptoms manifest themselves over an extended period of time. In any event, degeneration over time often results in a loss of disc support, and treatment is required to reduce or eliminate pain, such as immobilization to strengthen a portion of the spine.
Immobilization of a spinal column is often prescribed for treating a spinal condition. Swelling or pressure on the spinal column can create temporary problems that may become permanent if not properly addressed. Similarly, removal of a diseased portion of the spine or surrounding tissue may make the spine vulnerable to damage. In the event of a degenerative condition, treatment is required at some point to eliminate pain or to reduce the likelihood of a catastrophic failure. A number of approaches have been developed for this immobilization.
The type of condition often suggests the technique employed for treatment. For instance, damage to a nucleus may be minimal, which invites a treatment that attempts to repair the nucleus. A fractured vertebra would likely be braced in some way, such as with a bone plate, to immobilize the vertebral segments to encourage the fracture to heal.
In some cases, a manner of treating spinal conditions is known as spinal fusion surgery. Two or more vertebrae may be fused or immobilized relative to each other to maintain the intervertebral distance, to maintain or replicate the integrity of the spine for support, and to prevent rotation or flexion between the affected vertebrae. Though such a prescription results in some loss of movement and flexibility to the spine, it is seen as a suitable manner for protecting the spine and spinal cord from injury and reducing pain from compression on the spinal cord. Moreover, the other, unaffected spinal portions may compensate to provide most of the normal movement.
Accordingly, there has been a need for improved spinal fusion systems and for improved methods for performing spinal fusion surgery.